1
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Xu X, Wu G. Protocol to visualize and quantify the COPII concentration and anterograde transport of nascent G protein-coupled receptors. STAR Protoc 2024; 5:102955. [PMID: 38489271 PMCID: PMC10951583 DOI: 10.1016/j.xpro.2024.102955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 01/31/2024] [Accepted: 02/28/2024] [Indexed: 03/17/2024] Open
Abstract
Here, we present a protocol for visualization and quantification of the recruitment of newly synthesized G protein-coupled receptors (GPCRs) to coat protein complex II vesicles and GPCR transport from the endoplasmic reticulum through the Golgi to the cell surface in the retention using the selective hooks assay. We describe steps for plasmid construction, cell transfection, transport synchronization, confocal microscope imaging, and quantification. This protocol is also applicable for studying the transport of non-GPCR cargoes. For complete details on the use and execution of this protocol, please refer to Xu et al.1,2.
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Affiliation(s)
- Xin Xu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
| | - Guangyu Wu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
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2
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Su LY, Jiao L, Liu Q, Qiao X, Xie T, Ma Z, Xu M, Ye MS, Yang LX, Chen C, Yao YG. S-nitrosoglutathione reductase alleviates morphine analgesic tolerance by restricting PKCα S-nitrosation. Redox Biol 2024; 75:103239. [PMID: 38901102 PMCID: PMC11253161 DOI: 10.1016/j.redox.2024.103239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Accepted: 06/13/2024] [Indexed: 06/22/2024] Open
Abstract
Morphine, a typical opiate, is widely used for controlling pain but can lead to various side effects with long-term use, including addiction, analgesic tolerance, and hyperalgesia. At present, however, the mechanisms underlying the development of morphine analgesic tolerance are not fully understood. This tolerance is influenced by various opioid receptor and kinase protein modifications, such as phosphorylation and ubiquitination. Here, we established a murine morphine tolerance model to investigate whether and how S-nitrosoglutathione reductase (GSNOR) is involved in morphine tolerance. Repeated administration of morphine resulted in the down-regulation of GSNOR, which increased excessive total protein S-nitrosation in the prefrontal cortex. Knockout or chemical inhibition of GSNOR promoted the development of morphine analgesic tolerance and neuron-specific overexpression of GSNOR alleviated morphine analgesic tolerance. Mechanistically, GSNOR deficiency enhanced S-nitrosation of cellular protein kinase alpha (PKCα) at the Cys78 and Cys132 sites, leading to inhibition of PKCα kinase activity, which ultimately promoted the development of morphine analgesic tolerance. Our study highlighted the significant role of GSNOR as a key regulator of PKCα S-nitrosation and its involvement in morphine analgesic tolerance, thus providing a potential therapeutic target for morphine tolerance.
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Affiliation(s)
- Ling-Yan Su
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; College of Food Science and Technology, and Yunnan Key Laboratory of Precision Nutrition and Personalized Food Manufacturing, Yunnan Agricultural University, Kunming, Yunnan, 650201, China
| | - Lijin Jiao
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Qianjin Liu
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Xinhua Qiao
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ting Xie
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhiyu Ma
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Min Xu
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Mao-Sen Ye
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Lu-Xiu Yang
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China
| | - Chang Chen
- Key Laboratory of Biomacromolecules (CAS), National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Yong-Gang Yao
- Key Laboratory of Genetic Evolution and Animal Models of the Chinese Academy of Sciences, Yunnan Key Laboratory of Animal Models and Human Disease Mechanisms, and KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, Yunnan, 650204, China; National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), National Resource Center for Non-Human Primates, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650107, China.
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3
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Thomas P, Pang Y, Kelder J. Membrane progesterone receptors on the cell membrane: A review highlighting potential export motifs in mPRα regulating its trafficking to the cell surface. Steroids 2023; 199:109295. [PMID: 37558174 DOI: 10.1016/j.steroids.2023.109295] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/03/2023] [Accepted: 08/05/2023] [Indexed: 08/11/2023]
Abstract
Substantial progress has been made in our understanding of the nongenomic actions, ligand binding, intracellular signaling pathways, and functions of membrane progesterone receptors (mPRs) in reproductive and nonreproductive tissues since their discovery 20 years ago. The five mPRs are members of the progestin adipoQ receptor (PAQR) family which also includes adiponectin receptors (AdipoRs). However, unlike AdipoRs, the 3-D structures of mPRs are unknown, and their structural characteristics remain poorly understood. The mechanisms regulating mPR functions and their trafficking to the cell surface have received little attention and have not been systematically reviewed. This paper summarizes some structural aspects of mPRs, including the ligand binding pocket of mPRα recently derived from homology modeling with AdipoRs, and the proposed topology of mPRs from the preponderance of positively charged amino acid residues in their intracellular domains. The mechanisms of trafficking membrane receptors to the cell surface are discussed, including the amino acid motifs involved with their export to the cell surface, the roles of adaptor proteins, and post-translational glycosylation and palmitoylation modifications that promote cell surface expression and retention. Evidence for similar mechanisms regulating the expression and functions of mPRs on the cell surface is discussed, including the identification of potential export motifs on mPRα required for its trafficking to the cell membrane. Collectively, these results have identified several potential mechanisms regulating the expression and functions of mPRs on the cell membrane for further investigation.
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Affiliation(s)
- Peter Thomas
- University of Texas at Austin Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA.
| | - Yefei Pang
- University of Texas at Austin Marine Science Institute, 750 Channel View Drive, Port Aransas, TX 78373, USA
| | - Jan Kelder
- Theoretical & Computational Chemistry, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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4
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Jaster AM, González-Maeso J. Mechanisms and molecular targets surrounding the potential therapeutic effects of psychedelics. Mol Psychiatry 2023; 28:3595-3612. [PMID: 37759040 DOI: 10.1038/s41380-023-02274-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023]
Abstract
Psychedelics, also known as classical hallucinogens, have been investigated for decades due to their potential therapeutic effects in the treatment of neuropsychiatric and substance use disorders. The results from clinical trials have shown promise for the use of psychedelics to alleviate symptoms of depression and anxiety, as well as to promote substantial decreases in the use of nicotine and alcohol. While these studies provide compelling evidence for the powerful subjective experience and prolonged therapeutic adaptations, the underlying molecular reasons for these robust and clinically meaningful improvements are still poorly understood. Preclinical studies assessing the targets and circuitry of the post-acute effects of classical psychedelics are ongoing. Current literature is split between a serotonin 5-HT2A receptor (5-HT2AR)-dependent or -independent signaling pathway, as researchers are attempting to harness the mechanisms behind the sustained post-acute therapeutically relevant effects. A combination of molecular, behavioral, and genetic techniques in neuropharmacology has begun to show promise for elucidating these mechanisms. As the field progresses, increasing evidence points towards the importance of the subjective experience induced by psychedelic-assisted therapy, but without further cross validation between clinical and preclinical research, the why behind the experience and its translational validity may be lost.
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Affiliation(s)
- Alaina M Jaster
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
- Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA
| | - Javier González-Maeso
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA, 23298, USA.
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5
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Ashton AW. Preparing to strike: Acute events in signaling by the serpentine receptor for thromboxane A 2. Pharmacol Ther 2023:108478. [PMID: 37321373 DOI: 10.1016/j.pharmthera.2023.108478] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/31/2023] [Accepted: 06/07/2023] [Indexed: 06/17/2023]
Abstract
Over the last two decades, awareness of the (patho)physiological roles of thromboxane A2 signaling has been greatly extended. From humble beginnings as a short-lived stimulus that activates platelets and causes vasoconstriction to a dichotomous receptor system involving multiple endogenous ligands capable of modifying tissue homeostasis and disease generation in almost every tissue of the body. Thromboxane A2 receptor (TP) signal transduction is associated with the pathogenesis of cancer, atherosclerosis, heart disease, asthma, and host response to parasitic infection amongst others. The two receptors mediating these cellular responses (TPα and TPβ) are derived from a single gene (TBXA2R) through alternative splicing. Recently, knowledge about the mechanism(s) of signal propagation by the two receptors has undergone a revolution in understanding. Not only have the structural relationships associated with G-protein coupling been established but the modulation of that signaling by post-translational modification to the receptor has come sharply into focus. Moreover, the signaling of the receptor unrelated to G-protein coupling has become a burgeoning field of endeavor with over 70 interacting proteins currently identified. These data are reshaping the concept of TP signaling from a mere guanine nucleotide exchange factors for Gα activation to a nexus for the convergence of diverse and poorly characterized signaling pathways. This review summarizes the advances in understanding in TP signaling, and the potential for new growth in a field that after almost 50 years is finally coming of age.
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Affiliation(s)
- Anthony W Ashton
- Division of Cardiovascular Medicine, Lankenau Institute for Medical Research, Rm 128, 100 E Lancaster Ave, Wynnewood, PA 19096, USA; Division of Perinatal Research, Kolling Institute of Medical Research, Faculty of Medicine and Health, University of Sydney, St Leonards, NSW 2065, Australia.
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6
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Vargas MV, Dunlap LE, Dong C, Carter SJ, Tombari RJ, Jami SA, Cameron LP, Patel SD, Hennessey JJ, Saeger HN, McCorvy JD, Gray JA, Tian L, Olson DE. Psychedelics promote neuroplasticity through the activation of intracellular 5-HT2A receptors. Science 2023; 379:700-706. [PMID: 36795823 PMCID: PMC10108900 DOI: 10.1126/science.adf0435] [Citation(s) in RCA: 103] [Impact Index Per Article: 103.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/09/2023] [Indexed: 02/18/2023]
Abstract
Decreased dendritic spine density in the cortex is a hallmark of several neuropsychiatric diseases, and the ability to promote cortical neuron growth has been hypothesized to underlie the rapid and sustained therapeutic effects of psychedelics. Activation of 5-hydroxytryptamine (serotonin) 2A receptors (5-HT2ARs) is essential for psychedelic-induced cortical plasticity, but it is currently unclear why some 5-HT2AR agonists promote neuroplasticity, whereas others do not. We used molecular and genetic tools to demonstrate that intracellular 5-HT2ARs mediate the plasticity-promoting properties of psychedelics; these results explain why serotonin does not engage similar plasticity mechanisms. This work emphasizes the role of location bias in 5-HT2AR signaling, identifies intracellular 5-HT2ARs as a therapeutic target, and raises the intriguing possibility that serotonin might not be the endogenous ligand for intracellular 5-HT2ARs in the cortex.
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Affiliation(s)
- Maxemiliano V. Vargas
- Neuroscience Graduate Program, University of California, Davis; Davis, CA 95618, USA
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
| | - Lee E. Dunlap
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Department of Chemistry, University of California, Davis; Davis, CA 95616, USA
| | - Chunyang Dong
- Biochemistry, Molecular, Cellular, and Developmental Biology Graduate Program, University of California, Davis; Davis, CA 95616, USA
| | - Samuel J. Carter
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Department of Chemistry, University of California, Davis; Davis, CA 95616, USA
| | - Robert J. Tombari
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Department of Chemistry, University of California, Davis; Davis, CA 95616, USA
| | - Shekib A. Jami
- Center for Neuroscience, University of California, Davis; Davis, CA 95618, USA
| | - Lindsay P. Cameron
- Neuroscience Graduate Program, University of California, Davis; Davis, CA 95618, USA
| | - Seona D. Patel
- Department of Chemistry, University of California, Davis; Davis, CA 95616, USA
| | - Joseph J. Hennessey
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin; Milwaukee, WI 53226, USA
| | - Hannah N. Saeger
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Pharmacology and Toxicology Graduate Program, University of California, Davis; Davis, CA 95616, USA
| | - John D. McCorvy
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin; Milwaukee, WI 53226, USA
| | - John A. Gray
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Center for Neuroscience, University of California, Davis; Davis, CA 95618, USA
- Department of Neurology, School of Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Lin Tian
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Center for Neuroscience, University of California, Davis; Davis, CA 95618, USA
- Department of Biochemistry & Molecular Medicine, School of Medicine, University of California, Davis; Sacramento, CA 95817, USA
| | - David E. Olson
- Institute for Psychedelics and Neurotherapeutics, University of California, Davis, Davis, CA 95618, USA
- Department of Chemistry, University of California, Davis; Davis, CA 95616, USA
- Center for Neuroscience, University of California, Davis; Davis, CA 95618, USA
- Department of Biochemistry & Molecular Medicine, School of Medicine, University of California, Davis; Sacramento, CA 95817, USA
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7
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Jiang Y, Thienpont B, Sapuru V, Hite RK, Dittman JS, Sturgis JN, Scheuring S. Membrane-mediated protein interactions drive membrane protein organization. Nat Commun 2022; 13:7373. [PMID: 36450733 PMCID: PMC9712761 DOI: 10.1038/s41467-022-35202-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 11/22/2022] [Indexed: 12/02/2022] Open
Abstract
The plasma membrane's main constituents, i.e., phospholipids and membrane proteins, are known to be organized in lipid-protein functional domains and supercomplexes. No active membrane-intrinsic process is known to establish membrane organization. Thus, the interplay of thermal fluctuations and the biophysical determinants of membrane-mediated protein interactions must be considered to understand membrane protein organization. Here, we used high-speed atomic force microscopy and kinetic and membrane elastic theory to investigate the behavior of a model membrane protein in oligomerization and assembly in controlled lipid environments. We find that membrane hydrophobic mismatch modulates oligomerization and assembly energetics, and 2D organization. Our experimental and theoretical frameworks reveal how membrane organization can emerge from Brownian diffusion and a minimal set of physical properties of the membrane constituents.
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Affiliation(s)
- Yining Jiang
- Biochemistry & Structural Biology, Cell & Developmental Biology, and Molecular Biology (BCMB) Program, Weill Cornell Graduate School of Biomedical Sciences, 1300 York Avenue, New York, NY 10065 USA ,grid.5386.8000000041936877XWeill Cornell Medicine, Department of Anesthesiology, 1300 York Avenue, New York, NY 10065 USA
| | - Batiste Thienpont
- grid.5399.60000 0001 2176 4817Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM), Unité Mixte de Recherche (UMR) 7255, Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université, Marseille, France
| | - Vinay Sapuru
- grid.51462.340000 0001 2171 9952Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 USA ,Physiology, Biophysics, and Systems Biology (PBSB) Program, Weill Cornell Graduate School of Biomedical Sciences, 1300 York Avenue, New York, NY 10065 USA
| | - Richard K. Hite
- grid.51462.340000 0001 2171 9952Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 USA
| | - Jeremy S. Dittman
- grid.5386.8000000041936877XWeill Cornell Medicine, Department of Biochemistry, 1300 York Avenue, New York, NY 10065 USA
| | - James N. Sturgis
- grid.5399.60000 0001 2176 4817Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM), Unité Mixte de Recherche (UMR) 7255, Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université, Marseille, France
| | - Simon Scheuring
- grid.5386.8000000041936877XWeill Cornell Medicine, Department of Anesthesiology, 1300 York Avenue, New York, NY 10065 USA ,grid.5386.8000000041936877XWeill Cornell Medicine, Department of Physiology and Biophysics, 1300 York Avenue, New York, NY 10065 USA ,grid.5386.8000000041936877XKavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853 USA
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8
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Pal S, Gashev A, Roy D. Nuclear localization of histamine receptor 2 in primary human lymphatic endothelial cells. Biol Open 2022; 11:bio059191. [PMID: 35776777 PMCID: PMC9257380 DOI: 10.1242/bio.059191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 05/25/2022] [Indexed: 11/22/2022] Open
Abstract
Histamine exerts its physiological functions through its four receptor subtypes. In this work, we report the subcellular localization of histamine receptor 2 (H2R), a G protein-coupled receptor (GPCR), which is expressed in a wide variety of cell and tissue types. A growing number of GPCRs have been shown to be localized in the nucleus and contribute toward transcriptional regulation. In this study, for the first time, we demonstrate the nuclear localization of H2R in lymphatic endothelial cells. In the presence of its ligand, we show significant upregulation of H2R nuclear translocation kinetics. Using fluorescently tagged histamine, we explored H2R-histamine binding interaction, which exhibits a critical role in this translocation event. Altogether, our results highlight the previously unrecognized nuclear localization pattern of H2R. At the same time, H2R as a GPCR imparts many unresolved questions, such as the functional relevance of this localization, and whether H2R can contribute directly to transcriptional regulation and can affect lymphatic specific gene expression. H2R blockers are commonly used medications that recently have shown significant side effects. Therefore, it is imperative to understand the precise molecular mechanism of H2R biology. In this aspect, our present data shed new light on the unexplored H2R signaling mechanisms. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Sarit Pal
- Department of Medical Physiology, College of Medicine, Texas A&M University, Bryan, TX 77843, USA
| | - Anatoliy Gashev
- Department of Medical Physiology, College of Medicine, Texas A&M University, Bryan, TX 77843, USA
| | - Debarshi Roy
- Department of Biological Sciences, Alcorn State University, Lorman, MS 39096, USA
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9
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Thomas P. Membrane Progesterone Receptors (mPRs, PAQRs): Review of Structural and Signaling Characteristics. Cells 2022; 11:cells11111785. [PMID: 35681480 PMCID: PMC9179843 DOI: 10.3390/cells11111785] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/17/2022] [Accepted: 05/21/2022] [Indexed: 02/05/2023] Open
Abstract
The role of membrane progesterone receptors (mPRs), which belong to the progestin and adipoQ receptor (PAQR) family, in mediating rapid, nongenomic (non-classical) progestogen actions has been extensively studied since their identification 20 years ago. Although the mPRs have been implicated in progestogen regulation of numerous reproductive and non-reproductive functions in vertebrates, several critical aspects of their structure and signaling functions have been unresolved until recently and remain the subject of considerable debate. This paper briefly reviews recent developments in our understanding of the structure and functional characteristics of mPRs. The proposed membrane topology of mPRα, the structure of its ligand-binding site, and the binding affinities of steroids were predicted from homology modeling based on the structures of other PAQRs, adiponectin receptors, and confirmed by mutational analysis and ligand-binding assays. Extensive data demonstrating that mPR-dependent progestogen regulation of intracellular signaling through mPRs is mediated by activation of G proteins are reviewed. Close association of mPRα with progesterone membrane receptor component 1 (PGRMC1), its role as an adaptor protein to mediate cell-surface expression of mPRα and mPRα-dependent progestogen signaling has been demonstrated in several vertebrate models. In addition, evidence is presented that mPRs can regulate the activity of other hormone receptors.
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Affiliation(s)
- Peter Thomas
- Marine Science Institute, The University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, USA
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10
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Xu X, Wu G. Human C1orf27 protein interacts with α 2A-adrenergic receptor and regulates its anterograde transport. J Biol Chem 2022; 298:102021. [PMID: 35551911 PMCID: PMC9168726 DOI: 10.1016/j.jbc.2022.102021] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 11/25/2022] Open
Abstract
The molecular mechanisms underlying the anterograde surface transport of G protein–coupled receptors (GPCRs) after their synthesis in the endoplasmic reticulum (ER) are not well defined. In C. elegans, odorant response abnormal 4 has been implicated in the delivery of olfactory GPCRs to the cilia of chemosensory neurons. However, the function and regulation of its human homolog, C1orf27, in GPCR transport or in general membrane trafficking remain unknown. Here, we demonstrate that siRNA-mediated knockdown of C1orf27 markedly impedes the ER-to-Golgi export kinetics of newly synthesized α2A-adrenergic receptor (α2A-AR), a prototypic GPCR, with the half-time being prolonged by more than 65%, in mammalian cells in retention using the selective hooks assays. Using modified bioluminescence resonance energy transfer assays and ELISAs, we also show that C1orf27 knockdown significantly inhibits the surface transport of α2A-AR. Similarly, C1orf27 knockout by CRISPR-Cas9 markedly suppresses the ER–Golgi-surface transport of α2A-AR. In addition, we demonstrate that C1orf27 depletion attenuates the export of β2-AR and dopamine D2 receptor but not of epidermal growth factor receptor. We further show that C1orf27 physically associates with α2A-AR, specifically via its third intracellular loop and C terminus. Taken together, these data demonstrate an important role of C1orf27 in the trafficking of nascent GPCRs from the ER to the cell surface through the Golgi and provide novel insights into the regulation of the biosynthesis and anterograde transport of the GPCR family members.
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Affiliation(s)
- Xin Xu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Guangyu Wu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, Georgia, USA.
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11
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Sutton C, Williams EQ, Homsi H, Beerepoot P, Nazari R, Han D, Ramsey AJ, Mash DC, Olson DE, Blough B, Salahpour A. Structure-Activity Relationships of Dopamine Transporter Pharmacological Chaperones. Front Cell Neurosci 2022; 16:832536. [PMID: 35614973 PMCID: PMC9124866 DOI: 10.3389/fncel.2022.832536] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/21/2022] [Indexed: 11/13/2022] Open
Abstract
Mutations in the dopamine transporter gene (SLC6A3) have been implicated in many human diseases. Among these is the infantile parkinsonism-dystonia known as Dopamine Transporter Deficiency Syndrome (DTDS). Afflicted individuals have minimal to no functional dopamine transporter protein. This is primarily due to retention of misfolded disease-causing dopamine transporter variants. This results in a variety of severe motor symptoms in patients and the disease ultimately leads to death in adolescence or young adulthood. Though no treatment is currently available, pharmacological chaperones targeting the dopamine transporter have been shown to rescue select DTDS disease-causing variants. Previous work has identified two DAT pharmacological chaperones with moderate potency and efficacy: bupropion and ibogaine. In this study, we carried out structure-activity relationships (SARs) for bupropion and ibogaine with the goal of identifying the chemical features required for pharmacological chaperone activity. Our results show that the isoquinuclidine substituent of ibogaine and its analogs is an important feature for pharmacological chaperone efficacy. For bupropion, the secondary amine group is essential for pharmacological chaperone activity. Lastly, we describe additional ibogaine and bupropion analogs with varying chemical modifications and variable pharmacological chaperone efficacies at the dopamine transporter. Our results contribute to the design and refinement of future dopamine transporter pharmacological chaperones with improved efficacies and potencies.
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Affiliation(s)
- Charles Sutton
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Erin Q. Williams
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Hoomam Homsi
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Pieter Beerepoot
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Reza Nazari
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Dong Han
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Amy J. Ramsey
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Deborah C. Mash
- Departments of Neurology and Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - David E. Olson
- Department of Chemistry, College of Letters and Science, University of California, Davis, Davis, CA, United States
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Davis, CA, United States
- Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Bruce Blough
- Center for Drug Discovery, RTI International, North Carolina, NC, United States
| | - Ali Salahpour
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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12
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Anderson RC, Hanyroup S, Song YB, Mohamed-Moosa Z, van den Bout I, Schwulst AC, Kaiser UB, Millar RP, Newton CL. Functional Rescue of Inactivating Mutations of the Human Neurokinin 3 Receptor Using Pharmacological Chaperones. Int J Mol Sci 2022; 23:ijms23094587. [PMID: 35562976 PMCID: PMC9100388 DOI: 10.3390/ijms23094587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 12/04/2022] Open
Abstract
G protein-coupled receptors (GPCRs) facilitate the majority of signal transductions across cell membranes in humans, with numerous diseases attributed to inactivating GPCR mutations. Many of these mutations result in misfolding during nascent receptor synthesis in the endoplasmic reticulum (ER), resulting in intracellular retention and degradation. Pharmacological chaperones (PCs) are cell-permeant small molecules that can interact with misfolded receptors in the ER and stabilise/rescue their folding to promote ER exit and trafficking to the cell membrane. The neurokinin 3 receptor (NK3R) plays a pivotal role in the hypothalamic–pituitary–gonadal reproductive axis. We sought to determine whether NK3R missense mutations result in a loss of cell surface receptor expression and, if so, whether a cell-permeant small molecule NK3R antagonist could be repurposed as a PC to restore function to these mutants. Quantitation of cell surface expression levels of seven mutant NK3Rs identified in hypogonadal patients indicated that five had severely impaired cell surface expression. A small molecule NK3R antagonist, M8, increased cell surface expression in four of these five and resulted in post-translational receptor processing in a manner analogous to the wild type. Importantly, there was a significant improvement in receptor activation in response to neurokinin B (NKB) for all four receptors following their rescue with M8. This demonstrates that M8 may have potential for therapeutic development in the treatment of hypogonadal patients harbouring NK3R mutations. The repurposing of existing small molecule GPCR modulators as PCs represents a novel and therapeutically viable option for the treatment of disorders attributed to mutations in GPCRs that cause intracellular retention.
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Affiliation(s)
- Ross C. Anderson
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Correspondence:
| | - Sharika Hanyroup
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Yong Bhum Song
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Y.B.S.); (U.B.K.)
- Division of Research Center, Scripps Korea Antibody Institute, Chuncheon 24341, Korea
| | - Zulfiah Mohamed-Moosa
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Department of Anatomy and Physiology, Faculty of Veterinary Sciences, University of Pretoria, Private Bag X04, Pretoria 0110, South Africa
| | - Iman van den Bout
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Alexis C. Schwulst
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
| | - Ursula B. Kaiser
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (Y.B.S.); (U.B.K.)
| | - Robert P. Millar
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Department of Integrative Biomedical Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9JZ, UK
- School of Medicine, Medical and Biological Sciences Building, University of St Andrews, St Andrews KY16 9TF, UK
| | - Claire L. Newton
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa; (S.H.); (Z.M.-M.); (I.v.d.B.); (A.C.S.); (R.P.M.); (C.L.N.)
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0031, South Africa
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh EH8 9JZ, UK
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13
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Considerations on Using Antibodies for Studying the Dynorphins/Kappa Opioid Receptor System. Handb Exp Pharmacol 2022; 271:23-38. [PMID: 34085120 PMCID: PMC9125580 DOI: 10.1007/164_2021_467] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Antibodies are important tools for protein and peptide research, including for the kappa opioid receptor (KOR) and dynorphins (Dyns). Well-characterized antibodies are essential for rigorous and reproducible research. However, lack of validation of antibody specificity has been thought to contribute significantly to the reproducibility crisis in biomedical research. Since 2003, many scientific journals have required documentation of validation of antibody specificity and use of knockout mouse tissues as a negative control is strongly recommended. Lack of specificity of antibodies against many G protein-coupled receptors (GPCRs) after extensive testing has been well-documented, but antibodies generated against partial sequences of the KOR have not been similarly investigated. For the dynorphins, differential processing has been described in distinct brain areas, resulting in controversial findings in immunohistochemistry (IHC) when different antibodies were used. In this chapter, we summarized accepted approaches for validation of antibody specificity. We discussed two KOR antibodies most commonly used in IHC and described generation and characterization of KOR antibodies and phospho-KOR specific antibodies in western blotting or immunoblotting (IB). In addition, applying antibodies targeting prodynorphin or mature dynorphin A illustrates the diversity of results obtained regarding the distribution of dynorphins in distinct brain areas.
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14
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Membrane trafficking and positioning of mGluRs at presynaptic and postsynaptic sites of excitatory synapses. Neuropharmacology 2021; 200:108799. [PMID: 34592242 DOI: 10.1016/j.neuropharm.2021.108799] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 08/31/2021] [Accepted: 09/17/2021] [Indexed: 01/21/2023]
Abstract
The plethora of functions of glutamate in the brain are mediated by the complementary actions of ionotropic and metabotropic glutamate receptors (mGluRs). The ionotropic glutamate receptors carry most of the fast excitatory transmission, while mGluRs modulate transmission on longer timescales by triggering multiple intracellular signaling pathways. As such, mGluRs mediate critical aspects of synaptic transmission and plasticity. Interestingly, at synapses, mGluRs operate at both sides of the cleft, and thus bidirectionally exert the effects of glutamate. At postsynaptic sites, group I mGluRs act to modulate excitability and plasticity. At presynaptic sites, group II and III mGluRs act as auto-receptors, modulating release properties in an activity-dependent manner. Thus, synaptic mGluRs are essential signal integrators that functionally couple presynaptic and postsynaptic mechanisms of transmission and plasticity. Understanding how these receptors reach the membrane and are positioned relative to the presynaptic glutamate release site are therefore important aspects of synapse biology. In this review, we will discuss the currently known mechanisms underlying the trafficking and positioning of mGluRs at and around synapses, and how these mechanisms contribute to synaptic functioning. We will highlight outstanding questions and present an outlook on how recent technological developments will move this exciting research field forward.
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15
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Ulloa-Aguirre A, Zariñán T, Jardón-Valadez E. Misfolded G Protein-Coupled Receptors and Endocrine Disease. Molecular Mechanisms and Therapeutic Prospects. Int J Mol Sci 2021; 22:ijms222212329. [PMID: 34830210 PMCID: PMC8622668 DOI: 10.3390/ijms222212329] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 11/30/2022] Open
Abstract
Misfolding of G protein-coupled receptors (GPCRs) caused by mutations frequently leads to disease due to intracellular trapping of the conformationally abnormal receptor. Several endocrine diseases due to inactivating mutations in GPCRs have been described, including X-linked nephrogenic diabetes insipidus, thyroid disorders, familial hypocalciuric hypercalcemia, obesity, familial glucocorticoid deficiency [melanocortin-2 receptor, MC2R (also known as adrenocorticotropin receptor, ACTHR), and reproductive disorders. In these mutant receptors, misfolding leads to endoplasmic reticulum retention, increased intracellular degradation, and deficient trafficking of the abnormal receptor to the cell surface plasma membrane, causing inability of the receptor to interact with agonists and trigger intracellular signaling. In this review, we discuss the mechanisms whereby mutations in GPCRs involved in endocrine function in humans lead to misfolding, decreased plasma membrane expression of the receptor protein, and loss-of-function diseases, and also describe several experimental approaches employed to rescue trafficking and function of the misfolded receptors. Special attention is given to misfolded GPCRs that regulate reproductive function, given the key role played by these particular membrane receptors in sexual development and fertility, and recent reports on promising therapeutic interventions targeting trafficking of these defective proteins to rescue completely or partially their normal function.
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Affiliation(s)
- Alfredo Ulloa-Aguirre
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City 14080, Mexico;
- Correspondence:
| | - Teresa Zariñán
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City 14080, Mexico;
| | - Eduardo Jardón-Valadez
- Departamento de Recursos de la Tierra, Universidad Autónoma Metropolitana-Lerma, Lerma de Villada 52005, Estado de México, Mexico;
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16
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Degrandmaison J, Grisé O, Parent JL, Gendron L. Differential barcoding of opioid receptors trafficking. J Neurosci Res 2021; 100:99-128. [PMID: 34559903 DOI: 10.1002/jnr.24949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 07/25/2021] [Accepted: 08/05/2021] [Indexed: 11/09/2022]
Abstract
Over the past several years, studies have highlighted the δ-opioid receptor (DOPr) as a promising therapeutic target for chronic pain management. While exhibiting milder undesired effects than most currently prescribed opioids, its specific agonists elicit effective analgesic responses in numerous animal models of chronic pain, including inflammatory, neuropathic, diabetic, and cancer-related pain. However, as compared with the extensively studied μ-opioid receptor, the molecular mechanisms governing its trafficking remain elusive. Recent advances have denoted several significant particularities in the regulation of DOPr intracellular routing, setting it apart from the other members of the opioid receptor family. Although they share high homology, each opioid receptor subtype displays specific amino acid patterns potentially involved in the regulation of its trafficking. These precise motifs or "barcodes" are selectively recognized by regulatory proteins and therefore dictate several aspects of the itinerary of a receptor, including its anterograde transport, internalization, recycling, and degradation. With a specific focus on the regulation of DOPr trafficking, this review will discuss previously reported, as well as potential novel trafficking barcodes within the opioid and nociceptin/orphanin FQ opioid peptide receptors, and their impact in determining distinct interactomes and physiological responses.
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Affiliation(s)
- Jade Degrandmaison
- Département de Pharmacologie-Physiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Institut de Pharmacologie de Sherbrooke, Centre de Recherche du CHUS, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Quebec Network of Junior Pain Investigators, QC, Canada
| | - Olivier Grisé
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Institut de Pharmacologie de Sherbrooke, Centre de Recherche du CHUS, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Jean-Luc Parent
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Institut de Pharmacologie de Sherbrooke, Centre de Recherche du CHUS, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Institut de Pharmacologie de Sherbrooke, Centre de Recherche du CHUS, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada.,Quebec Pain Research Network, QC, Canada
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17
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Mattila SO, Tuhkanen HE, Lackman JJ, Konzack A, Morató X, Argerich J, Saftig P, Ciruela F, Petäjä-Repo UE. GPR37 is processed in the N-terminal ectodomain by ADAM10 and furin. FASEB J 2021; 35:e21654. [PMID: 34042202 DOI: 10.1096/fj.202002385rr] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 04/12/2021] [Accepted: 04/26/2021] [Indexed: 11/11/2022]
Abstract
GPR37 is an orphan G protein-coupled receptor (GPCR) implicated in several neurological diseases and important physiological pathways in the brain. We previously reported that its long N-terminal ectodomain undergoes constitutive metalloprotease-mediated cleavage and shedding, which have been rarely described for class A GPCRs. Here, we demonstrate that the protease that cleaves GPR37 at Glu167↓Gln168 is a disintegrin and metalloprotease 10 (ADAM10). This was achieved by employing selective inhibition, RNAi-mediated downregulation, and genetic depletion of ADAM10 in cultured cells as well as in vitro cleavage of the purified receptor with recombinant ADAM10. In addition, the cleavage was restored in ADAM10 knockout cells by overexpression of the wild type but not the inactive mutant ADAM10. Finally, postnatal conditional depletion of ADAM10 in mouse neuronal cells was found to reduce cleavage of the endogenous receptor in the brain cortex and hippocampus, confirming the physiological relevance of ADAM10 as a GPR37 sheddase. Additionally, we discovered that the receptor is subject to another cleavage step in cultured cells. Using site-directed mutagenesis, the site (Arg54↓Asp55) was localized to a highly conserved region at the distal end of the ectodomain that contains a recognition site for the proprotein convertase furin. The cleavage by furin was confirmed by using furin-deficient human colon carcinoma LoVo cells and proprotein convertase inhibitors. GPR37 is thus the first multispanning membrane protein that has been validated as an ADAM10 substrate and the first GPCR that is processed by both furin and ADAM10. The unconventional N-terminal processing may represent an important regulatory element for GPR37.
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Affiliation(s)
- S Orvokki Mattila
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, Oulu, Finland
| | - Hanna E Tuhkanen
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, Oulu, Finland
| | - Jarkko J Lackman
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, Oulu, Finland
| | - Anja Konzack
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, Oulu, Finland
| | - Xavier Morató
- Unitat de Farmacologia, Departament de Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, Universitat de Barcelona, Barcelona, Spain
| | - Josep Argerich
- Unitat de Farmacologia, Departament de Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, Universitat de Barcelona, Barcelona, Spain
| | - Paul Saftig
- Institute of Biochemistry, Kiel University, Kiel, Germany
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament de Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, Universitat de Barcelona, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Ulla E Petäjä-Repo
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, Oulu, Finland
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18
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Okamoto Y, Shikano S. Tyrosine sulfation and O-glycosylation of chemoattractant receptor GPR15 differentially regulate interaction with GPR15L. J Cell Sci 2021; 134:237784. [PMID: 33758080 DOI: 10.1242/jcs.247833] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 03/15/2021] [Indexed: 12/23/2022] Open
Abstract
GPR15 is a G-protein-coupled receptor (GPCR) that directs lymphocyte homing to the colon and skin. Recent studies have identified a chemokine-like protein GPR15L (also known as C10orf99) as a functional ligand of GPR15. In this study, we examined the structural elements that regulate the GPR15-GPR15L interaction with primary focus on post-translational modifications (PTMs) of receptor N-terminus and on the C-terminus of the ligand. Our findings reveal that the GPR15 receptor is sulfated on the N-terminal tyrosine residue(s) and disruption of tyrosine sulfation inhibits binding of GPR15L. In contrast, the disruption of O-glycosylation on the N-terminal threonine or serine residues, or the removal of α2,3-linked sialic acids from O-glycans, enhances the GPR15L binding. Thus, GPR15 represents a unique chemoattractant receptor in which different N-terminal PTMs regulate its ligand binding in a contrasting manner. We further demonstrate that, unlike canonical chemokines, GPR15L activity critically requires its extreme C-terminal residue and that its hydrophobicity may be a key attribute that facilitates an optimal interaction with the receptor. Our results reveal novel insights into chemoattractant receptor-ligand interaction and provide a valid footing for potential intervention targeting the GPR15-GPR15L axis.
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Affiliation(s)
- Yukari Okamoto
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607-7170, USA
| | - Sojin Shikano
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607-7170, USA
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19
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Park DD, Chen J, Kudelka MR, Jia N, Haller CA, Kosaraju R, Premji AM, Galizzi M, Nairn AV, Moremen KW, Cummings RD, Chaikof EL. Resident and elicited murine macrophages differ in expression of their glycomes and glycan-binding proteins. Cell Chem Biol 2021; 28:567-582.e4. [PMID: 33378651 PMCID: PMC8052306 DOI: 10.1016/j.chembiol.2020.12.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/17/2020] [Accepted: 12/08/2020] [Indexed: 12/20/2022]
Abstract
The pleiotropic functions of macrophages in immune defense, tissue repair, and maintenance of tissue homeostasis are supported by the heterogeneity in macrophage sub-populations that differ both in ontogeny and polarization. Although glycans and glycan-binding proteins (GBPs) are integral to macrophage function and may contribute to macrophage diversity, little is known about the factors governing their expression. Here, we provide a resource for characterizing the N-/O-glycomes of various murine peritoneal macrophage sub-populations, demonstrating that glycosylation primarily reflects developmental origin and, to a lesser degree, cellular polarization. Furthermore, comparative analysis of GBP-coding genes in resident and elicited macrophages indicated that GBP expression is consistent with specialized macrophage functions and correlates with specific types of displayed glycans. An integrated, semi-quantitative approach was used to confirm distinct expression patterns of glycans and their binding proteins across different macrophages. The data suggest that regulation of glycan-protein complexes may be central to macrophage residence and recruitment.
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Affiliation(s)
- Diane D Park
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Jiaxuan Chen
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Matthew R Kudelka
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Department of Biochemistry, Emory University, Atlanta, GA 30322, USA
| | - Nan Jia
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Carolyn A Haller
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Revanth Kosaraju
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Alykhan M Premji
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Melina Galizzi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Alison V Nairn
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Kelley W Moremen
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Richard D Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| | - Elliot L Chaikof
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA.
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20
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Patwardhan A, Cheng N, Trejo J. Post-Translational Modifications of G Protein-Coupled Receptors Control Cellular Signaling Dynamics in Space and Time. Pharmacol Rev 2021; 73:120-151. [PMID: 33268549 PMCID: PMC7736832 DOI: 10.1124/pharmrev.120.000082] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are a large family comprising >800 signaling receptors that regulate numerous cellular and physiologic responses. GPCRs have been implicated in numerous diseases and represent the largest class of drug targets. Although advances in GPCR structure and pharmacology have improved drug discovery, the regulation of GPCR function by diverse post-translational modifications (PTMs) has received minimal attention. Over 200 PTMs are known to exist in mammalian cells, yet only a few have been reported for GPCRs. Early studies revealed phosphorylation as a major regulator of GPCR signaling, whereas later reports implicated a function for ubiquitination, glycosylation, and palmitoylation in GPCR biology. Although our knowledge of GPCR phosphorylation is extensive, our knowledge of the modifying enzymes, regulation, and function of other GPCR PTMs is limited. In this review we provide a comprehensive overview of GPCR post-translational modifications with a greater focus on new discoveries. We discuss the subcellular location and regulatory mechanisms that control post-translational modifications of GPCRs. The functional implications of newly discovered GPCR PTMs on receptor folding, biosynthesis, endocytic trafficking, dimerization, compartmentalized signaling, and biased signaling are also provided. Methods to detect and study GPCR PTMs as well as PTM crosstalk are further highlighted. Finally, we conclude with a discussion of the implications of GPCR PTMs in human disease and their importance for drug discovery. SIGNIFICANCE STATEMENT: Post-translational modification of G protein-coupled receptors (GPCRs) controls all aspects of receptor function; however, the detection and study of diverse types of GPCR modifications are limited. A thorough understanding of the role and mechanisms by which diverse post-translational modifications regulate GPCR signaling and trafficking is essential for understanding dysregulated mechanisms in disease and for improving and refining drug development for GPCRs.
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Affiliation(s)
- Anand Patwardhan
- Department of Pharmacology and the Biomedical Sciences Graduate Program, School of Medicine, University of California, San Diego, La Jolla, California
| | - Norton Cheng
- Department of Pharmacology and the Biomedical Sciences Graduate Program, School of Medicine, University of California, San Diego, La Jolla, California
| | - JoAnn Trejo
- Department of Pharmacology and the Biomedical Sciences Graduate Program, School of Medicine, University of California, San Diego, La Jolla, California
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21
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Newton CL, Anderson RC, Kreuchwig A, Krause G, Katz AA, Millar RP. Rescue of Function of Mutant Luteinising Hormone Receptors with Deficiencies in Cell Surface Expression, Hormone Binding, and Hormone Signalling. Neuroendocrinology 2021; 111:451-464. [PMID: 32316022 DOI: 10.1159/000508000] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 04/18/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION G protein-coupled receptor (GPCR) mutations are implicated in many diseases. Most inactivating mutations cause receptor misfolding and prevent trafficking to the plasma membrane. Pharmacological chaperones can "rescue" cell surface expression of such mutants, presumably by stabilising correct folding of the nascent protein. OBJECTIVE Here we examine the scope of intracellularly retained luteinising hormone receptor (LHR) mutants that can be "rescued" by the pharmacological chaperone LHR-Chap, and whether this allosteric agonist can also restore the function of mutant LHRs with deficiencies in hormone binding or hormone-induced signalling. METHODS Mutant LHRs were expressed in HEK 293-T cells. Cell surface expression/localisation, hormone binding, and hCG/LHR-Chap signalling were determined by ELISA, radioligand binding, and inositol phosphate accumulation assays, respectively. Molecular modelling predicted LHR-Chap interactions. RESULTS LHR-Chap increased cell surface expression of a subset of retained mutants located in transmembrane helices predicted to be stabilised by LHR-Chap binding. For 3 (T4613.47I, L5024.61P, and S6167.46Y) hCG-responsiveness was increased following treatment. LHRs with mutations in the hormone-binding site (C131ECDR and I152ECDT) or in the hinge region (E354HingeK) had good cell surface expression but poor response to hormone stimulation, yet were responsive to allosteric activation by LHR-Chap. CONCLUSIONS LHR-Chap, in addition to rescuing cell surface expression of intracellularly retained LHR mutants, can rescue function in mutant receptors with binding and signalling deficiencies that have normal cell surface expression. This demonstration of rescue of multiple elements of LHR dysfunction arising from inactivating mutations offers exceptional potential for treating patients with diseases arising from GPCR mutations in general.
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Affiliation(s)
- Claire Louise Newton
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa,
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa,
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom,
| | - Ross Calley Anderson
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Annika Kreuchwig
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Gerd Krause
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Arieh Anthony Katz
- UCT Receptor Biology Research Unit and SAMRC Gynaecology Cancer Research Centre, Department of Integrative Biomedical Sciences and Institute of Infectious Diseases and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Robert Peter Millar
- Centre for Neuroendocrinology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
- Deanery of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
- School of Medicine, University of St Andrews, St Andrews, United Kingdom
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22
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Toneatti R, Shin JM, Shah UH, Mayer CR, Saunders JM, Fribourg M, Arsenovic PT, Janssen WG, Sealfon SC, López-Giménez JF, Benson DL, Conway DE, González-Maeso J. Interclass GPCR heteromerization affects localization and trafficking. Sci Signal 2020; 13:eaaw3122. [PMID: 33082287 PMCID: PMC7717648 DOI: 10.1126/scisignal.aaw3122] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Membrane trafficking processes regulate G protein-coupled receptor (GPCR) activity. Although class A GPCRs are capable of activating G proteins in a monomeric form, they can also potentially assemble into functional GPCR heteromers. Here, we showed that the class A serotonin 5-HT2A receptors (5-HT2ARs) affected the localization and trafficking of class C metabotropic glutamate receptor 2 (mGluR2) through a mechanism that required their assembly as heteromers in mammalian cells. In the absence of agonists, 5-HT2AR was primarily localized within intracellular compartments, and coexpression of 5-HT2AR with mGluR2 increased the intracellular distribution of the otherwise plasma membrane-localized mGluR2. Agonists for either 5-HT2AR or mGluR2 differentially affected trafficking through Rab5-positive endosomes in cells expressing each component of the 5-HT2AR-mGluR2 heterocomplex alone, or together. In addition, overnight pharmacological 5-HT2AR blockade with clozapine, but not with M100907, decreased mGluR2 density through a mechanism that involved heteromerization between 5-HT2AR and mGluR2. Using TAT-tagged peptides and chimeric constructs that are unable to form the interclass 5-HT2AR-mGluR2 complex, we demonstrated that heteromerization was necessary for the 5-HT2AR-dependent effects on mGluR2 subcellular distribution. The expression of 5-HT2AR also augmented intracellular localization of mGluR2 in mouse frontal cortex pyramidal neurons. Together, our data suggest that GPCR heteromerization may itself represent a mechanism of receptor trafficking and sorting.
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MESH Headings
- Amino Acids/pharmacology
- Animals
- Bridged Bicyclo Compounds, Heterocyclic/pharmacology
- Cell Membrane/metabolism
- Clozapine/pharmacology
- Endosomes/metabolism
- HEK293 Cells
- Humans
- Mice, 129 Strain
- Mice, Knockout
- Microscopy, Confocal
- Multiprotein Complexes/chemistry
- Multiprotein Complexes/metabolism
- Protein Multimerization
- Protein Transport/drug effects
- Receptor, Serotonin, 5-HT2A/chemistry
- Receptor, Serotonin, 5-HT2A/genetics
- Receptor, Serotonin, 5-HT2A/metabolism
- Receptors, Metabotropic Glutamate/chemistry
- Receptors, Metabotropic Glutamate/genetics
- Receptors, Metabotropic Glutamate/metabolism
- Serotonin Antagonists/pharmacology
- Signal Transduction
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Affiliation(s)
- Rudy Toneatti
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Jong M Shin
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Urjita H Shah
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Carl R Mayer
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, VA 23220, USA
| | - Justin M Saunders
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Miguel Fribourg
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Translational Transplant Research Center, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paul T Arsenovic
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, VA 23220, USA
| | - William G Janssen
- Department Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Stuart C Sealfon
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Juan F López-Giménez
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
- Instituto de Parasitología y Biomedicina "López-Neyra", CSIC, E-18016 Granada, Spain
| | - Deanna L Benson
- Department Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Daniel E Conway
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, VA 23220, USA
| | - Javier González-Maeso
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA.
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23
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Bubier JA, He H, Philip VM, Roy T, Hernandez CM, Bernat R, Donohue KD, O'Hara BF, Chesler EJ. Genetic variation regulates opioid-induced respiratory depression in mice. Sci Rep 2020; 10:14970. [PMID: 32917924 PMCID: PMC7486296 DOI: 10.1038/s41598-020-71804-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/11/2020] [Indexed: 12/14/2022] Open
Abstract
In the U.S., opioid prescription for treatment of pain nearly quadrupled from 1999 to 2014. The diversion and misuse of prescription opioids along with increased use of drugs like heroin and fentanyl, has led to an epidemic in addiction and overdose deaths. The most common cause of opioid overdose and death is opioid-induced respiratory depression (OIRD), a life-threatening depression in respiratory rate thought to be caused by stimulation of opioid receptors in the inspiratory-generating regions of the brain. Studies in mice have revealed that variation in opiate lethality is associated with strain differences, suggesting that sensitivity to OIRD is genetically determined. We first tested the hypothesis that genetic variation in inbred strains of mice influences the innate variability in opioid-induced responses in respiratory depression, recovery time and survival time. Using the founders of the advanced, high-diversity mouse population, the Diversity Outbred (DO), we found substantial sex and genetic effects on respiratory sensitivity and opiate lethality. We used DO mice treated with morphine to map quantitative trait loci for respiratory depression, recovery time and survival time. Trait mapping and integrative functional genomic analysis in GeneWeaver has allowed us to implicate Galnt11, an N-acetylgalactosaminyltransferase, as a gene that regulates OIRD.
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Affiliation(s)
| | - Hao He
- The Jackson Laboratory, Bar Harbor, ME, 04605, USA
| | | | - Tyler Roy
- The Jackson Laboratory, Bar Harbor, ME, 04605, USA
| | | | | | - Kevin D Donohue
- Signal Solutions, LLC, Lexington, KY, USA
- Electrical and Computer Engineering Department, University of Kentucky, Lexington, KY, USA
| | - Bruce F O'Hara
- Signal Solutions, LLC, Lexington, KY, USA
- Department of Biology, University of Kentucky, Lexington, KY, USA
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24
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Tao YX. Molecular chaperones and G protein-coupled receptor maturation and pharmacology. Mol Cell Endocrinol 2020; 511:110862. [PMID: 32389798 DOI: 10.1016/j.mce.2020.110862] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 05/04/2020] [Accepted: 05/05/2020] [Indexed: 12/15/2022]
Abstract
G protein-coupled receptors (GPCRs) are highly conserved versatile signaling molecules located at the plasma membrane that respond to diverse extracellular signals. They regulate almost all physiological processes in the vertebrates. About 35% of current drugs target these receptors. Mutations in these genes have been identified as causes of numerous diseases. The seven transmembrane domain structure of GPCRs implies that the folding of these transmembrane proteins is extremely complicated and difficult. Indeed, many wild type GPCRs are not folded optimally. The most common defect in genetic diseases caused by GPCR mutations is misfolding and failure to reach the plasma membrane where it functions. General molecular chaperones aid the folding of all proteins, including GPCRs, by preventing aggregation, promoting folding and disaggregating small aggregates. Some GPCRs need additional receptor-specific chaperones to assist their folding. Many of these receptor-specific chaperones interact with additional receptors and alter receptor pharmacology, expanding the understanding of these chaperone proteins.
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Affiliation(s)
- Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, 36849-5519, USA.
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25
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Lemos Duarte M, Devi LA. Post-translational Modifications of Opioid Receptors. Trends Neurosci 2020; 43:417-432. [PMID: 32459993 PMCID: PMC7323054 DOI: 10.1016/j.tins.2020.03.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 03/26/2020] [Accepted: 03/26/2020] [Indexed: 12/13/2022]
Abstract
Post-translational modifications (PTMs) are key events in signal transduction since they affect protein function by regulating their abundance and/or activity. PTMs involve the covalent attachment of functional groups to specific amino acids. Since they tend to be generally reversible, PTMs serve as regulators of signal transduction pathways. G-protein-coupled receptors (GPCRs) are major signaling proteins that undergo multiple types of PTMs. In this Review, we focus on the opioid receptors, members of GPCR family A, and highlight recent advances in the field that have underscored the importance of PTMs in the functional regulation of these receptors. Since opioid receptor activity plays a central role in the development of tolerance and addiction to morphine and other drugs of abuse, understanding the molecular mechanisms regulating receptor activity is of fundamental importance.
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Affiliation(s)
- Mariana Lemos Duarte
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lakshmi A Devi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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26
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Quirion B, Bergeron F, Blais V, Gendron L. The Delta-Opioid Receptor; a Target for the Treatment of Pain. Front Mol Neurosci 2020; 13:52. [PMID: 32431594 PMCID: PMC7214757 DOI: 10.3389/fnmol.2020.00052] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/13/2020] [Indexed: 12/15/2022] Open
Abstract
Nowadays, pain represents one of the most important societal burdens. Current treatments are, however, too often ineffective and/or accompanied by debilitating unwanted effects for patients dealing with chronic pain. Indeed, the prototypical opioid morphine, as many other strong analgesics, shows harmful unwanted effects including respiratory depression and constipation, and also produces tolerance, physical dependence, and addiction. The urgency to develop novel treatments against pain while minimizing adverse effects is therefore crucial. Over the years, the delta-opioid receptor (DOP) has emerged as a promising target for the development of new pain therapies. Indeed, targeting DOP to treat chronic pain represents a timely alternative to existing drugs, given the weak unwanted effects spectrum of DOP agonists. Here, we review the current knowledge supporting a role for DOP and its agonists for the treatment of pain. More specifically, we will focus on the cellular and subcellular localization of DOP in the nervous system. We will also discuss in further detail the molecular and cellular mechanisms involved in controlling the cellular trafficking of DOP, known to differ significantly from most G protein-coupled receptors. This review article will allow a better understanding of how DOP represents a promising target to develop new treatments for pain management as well as where we stand as of our ability to control its cellular trafficking and cell surface expression.
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Affiliation(s)
- Béatrice Quirion
- Faculté de Médecine et des Sciences de la Santé, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Francis Bergeron
- Faculté de Médecine et des Sciences de la Santé, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Véronique Blais
- Faculté de Médecine et des Sciences de la Santé, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Louis Gendron
- Faculté de Médecine et des Sciences de la Santé, Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada
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27
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Janezic EM, Lauer SML, Williams RG, Chungyoun M, Lee KS, Navaluna E, Lau HT, Ong SE, Hague C. N-glycosylation of α 1D-adrenergic receptor N-terminal domain is required for correct trafficking, function, and biogenesis. Sci Rep 2020; 10:7209. [PMID: 32350295 PMCID: PMC7190626 DOI: 10.1038/s41598-020-64102-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/09/2020] [Indexed: 01/21/2023] Open
Abstract
G protein-coupled receptor (GPCR) biogenesis, trafficking, and function are regulated by post-translational modifications, including N-glycosylation of asparagine residues. α1D-adrenergic receptors (α1D-ARs) - key regulators of central and autonomic nervous system function - contain two putative N-glycosylation sites within the large N-terminal domain at N65 and N82. However, determining the glycosylation state of this receptor has proven challenging. Towards understanding the role of these putative glycosylation sites, site-directed mutagenesis and lectin affinity purification identified N65 and N82 as bona fide acceptors for N-glycans. Surprisingly, we also report that simultaneously mutating N65 and N82 causes early termination of α1D-AR between transmembrane domain 2 and 3. Label-free dynamic mass redistribution and cell surface trafficking assays revealed that single and double glycosylation deficient mutants display limited function with impaired plasma membrane expression. Confocal microscopy imaging analysis and SNAP-tag sucrose density fractionation assays revealed the dual glycosylation mutant α1D-AR is widely distributed throughout the cytosol and nucleus. Based on these novel findings, we propose α1D-AR transmembrane domain 2 acts as an ER localization signal during active protein biogenesis, and that α1D-AR N-terminal glycosylation is required for complete translation of nascent, functional receptor.
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Affiliation(s)
- Eric M Janezic
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Sophia My-Linh Lauer
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Robert George Williams
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Michael Chungyoun
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Kyung-Soon Lee
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Edelmar Navaluna
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Ho-Tak Lau
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Shao-En Ong
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA
| | - Chris Hague
- Department of Pharmacology, School of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98185, USA.
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28
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Wang T, Nakagawa S, Miyake T, Setsu G, Kunisue S, Goto K, Hirasawa A, Okamura H, Yamaguchi Y, Doi M. Identification and functional characterisation of N-linked glycosylation of the orphan G protein-coupled receptor Gpr176. Sci Rep 2020; 10:4429. [PMID: 32157140 PMCID: PMC7064540 DOI: 10.1038/s41598-020-61370-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Accepted: 02/26/2020] [Indexed: 12/13/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are important drug targets with diverse therapeutic applications. However, there are still more than a hundred orphan GPCRs, whose protein functions and biochemical features remain unidentified. Gpr176 encodes a class-A orphan GPCR that has a role in circadian clock regulation in mouse hypothalamus and is also implicated in human breast cancer transcriptional response. Here we show that Gpr176 is N-glycosylated. Peptide-N-glycosidase treatment of mouse hypothalamus extracts revealed that endogenous Gpr176 undergoes N-glycosylation. Using a heterologous expression system, we show that N-glycosylation occurs at four conserved asparagine residues in the N-terminal region of Gpr176. Deficient N-glycosylation due to mutation of these residues reduced the protein expression of Gpr176. At the molecular function level, Gpr176 has constitutive, agonist-independent activity that leads to reduced cAMP synthesis. Although deficient N-glycosylation did not compromise this intrinsic activity, the resultant reduction in protein expression was accompanied by attenuation of cAMP-repressive activity in the cells. We also demonstrate that human GPR176 is N-glycosylated. Importantly, missense variations in the conserved N-glycosylation sites of human GPR176 (rs1473415441; rs761894953) affected N-glycosylation and thereby attenuated protein expression and cAMP-repressive activity in the cells. We show that N-glycosylation is a prerequisite for the efficient protein expression of functional Gpr176/GPR176.
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Affiliation(s)
- Tianyu Wang
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Shumpei Nakagawa
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Takahito Miyake
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Genzui Setsu
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Sumihiro Kunisue
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Kaoru Goto
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Akira Hirasawa
- Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Hitoshi Okamura
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan.,Laboratory of Molecular Brain Science, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Yoshiaki Yamaguchi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Masao Doi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan.
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29
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Zhu C, Han Q, Samoshkin A, Convertino M, Linton A, Faison EM, Ji RR, Diatchenko L, Dokholyan NV. Stabilization of μ-opioid receptor facilitates its cellular translocation and signaling. Proteins 2019; 87:878-884. [PMID: 31141214 DOI: 10.1002/prot.25751] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/09/2019] [Accepted: 05/26/2019] [Indexed: 01/01/2023]
Abstract
The G protein-coupled μ-opioid receptor (μ-OR) mediates the majority of analgesia effects for morphine and other pain relievers. Despite extensive studies of its structure and activation mechanisms, the inherently low maturation efficiency of μ-OR represents a major hurdle to understanding its function. Here we computationally designed μ-OR mutants with altered stability to probe the relationship between cell-surface targeting, signal transduction, and agonist efficacy. The stabilizing mutation T315Y enhanced μ-OR trafficking to the plasma membrane and significantly promoted the morphine-mediated inhibition of downstream signaling. In contrast, the destabilizing mutation R165Y led to intracellular retention of μ-OR and reduced the response to morphine stimulation. These findings suggest that μ-OR stability is an important factor in regulating receptor signaling and provide a viable avenue to improve the efficacy of analgesics.
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Affiliation(s)
- Cheng Zhu
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Pharmacology, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Qingjian Han
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina.,Department of Neurobiology, Duke University Medical Center, Durham, North Carolina
| | - Alexander Samoshkin
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada.,School of the Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Marino Convertino
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Alexander Linton
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Edgar M Faison
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Ru-Rong Ji
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina.,Department of Neurobiology, Duke University Medical Center, Durham, North Carolina
| | - Luda Diatchenko
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Nikolay V Dokholyan
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Pharmacology, Penn State University College of Medicine, Hershey, Pennsylvania.,Department of Biochemistry & Molecular Biology, Penn State University College of Medicine, Hershey, Pennsylvania.,Department of Biomedical Engineering, Penn State University, Pennsylvania.,Department of Chemistry, Penn State University, Pennsylvania
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30
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Shiwarski DJ, Crilly SE, Dates A, Puthenveedu MA. Dual RXR motifs regulate nerve growth factor-mediated intracellular retention of the delta opioid receptor. Mol Biol Cell 2019; 30:680-690. [PMID: 30601694 PMCID: PMC6589700 DOI: 10.1091/mbc.e18-05-0292] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 12/21/2018] [Accepted: 12/27/2018] [Indexed: 12/19/2022] Open
Abstract
The delta opioid receptor (DOR), a physiologically relevant prototype for G protein-coupled receptors, is retained in intracellular compartments in neuronal cells. This retention is mediated by a nerve growth factor (NGF)-regulated checkpoint that delays the export of DOR from the trans-Golgi network. How DOR is selectively retained in the Golgi, in the midst of dynamic membrane transport and cargo export, is a fundamental unanswered question. Here we address this by investigating sequence elements on DOR that regulate DOR surface delivery, focusing on the C-terminal tail of DOR that is sufficient for NGF-mediated regulation. By systematic mutational analysis, we define conserved dual bi-arginine (RXR) motifs that are required for NGF- and phosphoinositide-regulated DOR export from intracellular compartments in neuroendocrine cells. These motifs were required to bind the coatomer protein I (COPI) complex, a vesicle coat complex that mediates primarily retrograde cargo traffic in the Golgi. Our results suggest that interactions of DOR with COPI, via atypical COPI motifs on the C-terminal tail, retain DOR in the Golgi. These interactions could provide a point of regulation of DOR export and delivery by extracellular signaling pathways.
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Affiliation(s)
- Daniel J. Shiwarski
- Department of Biological Sciences, The Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Stephanie E. Crilly
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109
| | - Andrew Dates
- Department of Biological Sciences, The Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Manojkumar A. Puthenveedu
- Department of Biological Sciences, The Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109
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31
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Gendron L, Nagi K, Zeghal M, Giguère PM, Pineyro G. Molecular aspects of delta opioid receptors. OPIOID HORMONES 2019; 111:49-90. [DOI: 10.1016/bs.vh.2019.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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32
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Tao YX, Conn PM. Pharmacoperones as Novel Therapeutics for Diverse Protein Conformational Diseases. Physiol Rev 2018; 98:697-725. [PMID: 29442594 DOI: 10.1152/physrev.00029.2016] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
After synthesis, proteins are folded into their native conformations aided by molecular chaperones. Dysfunction in folding caused by genetic mutations in numerous genes causes protein conformational diseases. Membrane proteins are more prone to misfolding due to their more intricate folding than soluble proteins. Misfolded proteins are detected by the cellular quality control systems, especially in the endoplasmic reticulum, and proteins may be retained there for eventual degradation by the ubiquitin-proteasome system or through autophagy. Some misfolded proteins aggregate, leading to pathologies in numerous neurological diseases. In vitro, modulating mutant protein folding by altering molecular chaperone expression can ameliorate some misfolding. Some small molecules known as chemical chaperones also correct mutant protein misfolding in vitro and in vivo. However, due to their lack of specificity, their potential as therapeutics is limited. Another class of compounds, known as pharmacological chaperones (pharmacoperones), binds with high specificity to misfolded proteins, either as enzyme substrates or receptor ligands, leading to decreased folding energy barriers and correction of the misfolding. Because many of the misfolded proteins are misrouted but do not have defects in function per se, pharmacoperones have promising potential in advancing to the clinic as therapeutics, since correcting routing may ameliorate the underlying mechanism of disease. This review will comprehensively summarize this exciting area of research, surveying the literature from in vitro studies in cell lines to transgenic animal models and clinical trials in several protein misfolding diseases.
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Affiliation(s)
- Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University , Auburn, Alabama ; and Departments of Internal Medicine and Cell Biology, Texas Tech University Health Science Center , Lubbock, Texas
| | - P Michael Conn
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University , Auburn, Alabama ; and Departments of Internal Medicine and Cell Biology, Texas Tech University Health Science Center , Lubbock, Texas
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Alternative Splicing of the Delta-Opioid Receptor Gene Suggests Existence of New Functional Isoforms. Mol Neurobiol 2018; 56:2855-2869. [PMID: 30066306 DOI: 10.1007/s12035-018-1253-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/17/2018] [Indexed: 12/26/2022]
Abstract
The delta-opioid receptor (DOPr) participates in mediating the effects of opioid analgesics. However, no selective agonists have entered clinical care despite potential to ameliorate many neurological and psychiatric disorders. In an effort to address the drug development challenges, the functional contribution of receptor isoforms created by alternative splicing of the three-exonic coding gene, OPRD1, has been overlooked. We report that the gene is transcriptionally more diverse than previously demonstrated, producing novel protein isoforms in humans and mice. We provide support for the functional relevance of splice variants through context-dependent expression profiling (tissues, disease model) and conservation of the transcriptional landscape in closely related vertebrates. The conserved alternative transcriptional events have two distinct patterns. First, cassette exon inclusions between exons 1 and 2 interrupt the reading frame, producing truncated receptor fragments comprising only the first transmembrane (TM) domain, despite the lack of exact exon orthologues between distant species. Second, a novel promoter and transcriptional start site upstream of exon 2 produces a transcript of an N-terminally truncated 6TM isoform. However, a fundamental difference in the exonic landscaping as well as translation and translation products poses limits for modelling the human DOPr receptor system in mice.
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Abstract
Pharmacological chaperones (PCs) are small molecules that bind to nascent protein targets to facilitate their biogenesis. The ability of PCs to assist in the folding and subsequent forward trafficking of disease-causative protein misfolding mutants has opened new avenues for the treatment of conformational diseases such as cystic fibrosis and lysosomal storage disorders. In this chapter, an overview of the use of PCs for the treatment of conformational disorders is provided. Beyond the therapeutic application of PCs for the treatment of these disorders, pharmacological chaperoning of wild-type integral membrane proteins is discussed. Central to this discussion is the notion that the endoplasmic reticulum is a reservoir of viable but inefficiently processed wild-type protein folding intermediates whose biogenesis can be facilitated by PCs to increase functional pools. To date, the potential therapeutic use of PCs to enhance the biogenesis of wild-type proteins has received little attention. Here the rationale for the development of PCs that target WT proteins is discussed. Also considered is the likelihood that some commonly used therapeutic agents may exert unrecognized pharmacological chaperoning activity on wild-type targets in patient populations.
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Affiliation(s)
- Nancy J Leidenheimer
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center - Shreveport, Shreveport, LA, USA.
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Lackman JJ, Goth CK, Halim A, Vakhrushev SY, Clausen H, Petäjä-Repo UE. Site-specific O-glycosylation of N-terminal serine residues by polypeptide GalNAc-transferase 2 modulates human δ-opioid receptor turnover at the plasma membrane. Cell Signal 2018; 42:184-193. [PMID: 29097258 DOI: 10.1016/j.cellsig.2017.10.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/26/2017] [Accepted: 10/27/2017] [Indexed: 12/21/2022]
Abstract
G protein-coupled receptors (GPCRs) are an important protein family of signalling receptors that govern a wide variety of physiological functions. The capacity to transmit extracellular signals and the extent of cellular response are largely determined by the amount of functional receptors at the cell surface that is subject to complex and fine-tuned regulation. Here, we demonstrate that the cell surface expression level of an inhibitory GPCR, the human δ-opioid receptor (hδOR) involved in pain and mood regulation, is modulated by site-specific N-acetylgalactosamine (GalNAc) -type O-glycosylation. Importantly, we identified one out of the 20 polypeptide GalNAc-transferase isoforms, GalNAc-T2, as the specific regulator of O-glycosylation of Ser6, Ser25 and Ser29 in the N-terminal ectodomain of the receptor. This was demonstrated by in vitro glycosylation assays using peptides corresponding to the hδOR N-terminus, Vicia villosa lectin affinity purification of receptors expressed in HEK293 SimpleCells capable of synthesizing only truncated O-glycans, GalNAc-T edited cell line model systems, and site-directed mutagenesis of the putative O-glycosylation sites. Interestingly, a single-nucleotide polymorphism, at residue 27 (F27C), was found to alter O-glycosylation of the receptor in efficiency as well as in glycosite usage. Furthermore, flow cytometry and cell surface biotinylation assays using O-glycan deficient CHO-ldlD cells revealed that the absence of O-glycans results in decreased receptor levels at the plasma membrane due to enhanced turnover. In addition, mutation of the identified O-glycosylation sites led to a decrease in the number of ligand-binding competent receptors and impaired agonist-mediated inhibition of cyclic AMP accumulation in HEK293 cells. Thus, site-specific O-glycosylation by a selected GalNAc-T isoform can increase the stability of a GPCR, in a process that modulates the constitutive turnover and steady-state levels of functional receptors at the cell surface.
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MESH Headings
- Acetylgalactosamine/chemistry
- Acetylgalactosamine/metabolism
- Amino Acid Sequence
- Animals
- CHO Cells
- Cell Line, Tumor
- Cell Membrane/chemistry
- Cell Membrane/metabolism
- Chromatography, Affinity/methods
- Cricetulus
- Cyclic AMP/metabolism
- Glycosylation
- HEK293 Cells
- Hep G2 Cells
- Humans
- Mutagenesis, Site-Directed
- N-Acetylgalactosaminyltransferases/genetics
- N-Acetylgalactosaminyltransferases/metabolism
- Neurons/cytology
- Neurons/metabolism
- Peptides/chemical synthesis
- Peptides/metabolism
- Plant Lectins/chemistry
- Polymorphism, Single Nucleotide
- Protein Processing, Post-Translational
- Protein Stability
- Receptors, Opioid, delta/chemistry
- Receptors, Opioid, delta/genetics
- Receptors, Opioid, delta/metabolism
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Sequence Alignment
- Serine/metabolism
- Polypeptide N-acetylgalactosaminyltransferase
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Affiliation(s)
- Jarkko J Lackman
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, FI-90014 Oulu, Finland
| | - Christoffer K Goth
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Adnan Halim
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Sergey Y Vakhrushev
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Ulla E Petäjä-Repo
- Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, FI-90014 Oulu, Finland.
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Abstract
The gonadotropin receptors (luteinising hormone receptor; LHR and follicle-stimulating hormone receptor; FSHR) are G protein-coupled receptors (GPCRs) that play an important role in the endocrine control of reproduction. Thus genetic mutations that cause impaired function of these receptors have been implicated in a number of reproductive disorders. Disease-causing genetic mutations in GPCRs frequently result in intracellular retention and degradation of the nascent protein through misfolding and subsequent recognition by cellular quality control machinery. The discovery and development of novel compounds termed pharmacological chaperones (pharmacoperones) that can stabilise misfolded receptors and restore trafficking and plasma membrane expression are therefore of great interest clinically, and promising in vitro data describing the pharmacoperone rescue of a number of intracellularly retained mutant GPCRs has provided a platform for taking these compounds into in vivo trials. Thienopyrimidine small molecule allosteric gonadotropin receptor agonists (Org 42599 and Org 41841) have been demonstrated to have pharmacoperone activity. These compounds can rescue cell surface expression and in many cases, hormone responsiveness, of a range of retained mutant gonadotropin receptors. Should gonadotropin receptor selectivity of these compounds be improved, they could offer therapeutic benefit to subsets of patients suffering from reproductive disorders attributed to defective gonadotropin receptor trafficking.
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Affiliation(s)
- Claire L Newton
- Centre for Neuroendocrinology and Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria, 0001, South Africa.
| | - Ross C Anderson
- Centre for Neuroendocrinology and Department of Immunology, Faculty of Health Sciences, University of Pretoria, PO Box 2034, Pretoria, 0001, South Africa
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Leidenheimer NJ. Cognate Ligand Chaperoning: a Novel Mechanism for the Post-translational Regulation of Neurotransmitter Receptor Biogenesis. Front Cell Neurosci 2017; 11:245. [PMID: 28860972 PMCID: PMC5559506 DOI: 10.3389/fncel.2017.00245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 08/02/2017] [Indexed: 11/13/2022] Open
Abstract
The functional unit for inter-neuronal communication in the central nervous system is the neuronal synapse. The number of postsynaptic neurotransmitter receptors at the cell surface is an important determinant of synaptic efficacy and plasticity. A diverse array of post-translational processes regulate postsynaptic receptor number, including receptor exocytosis, lateral diffusion, surface stabilization, endocytosis, and recycling, thus highlighting the importance of mechanisms that control postsynaptic receptor levels. Another putative post-translational mechanism for regulating receptor surface expression is cognate ligand chaperoning. It has been proposed that neurotransmitters function as cognate ligand chaperones by binding, within the endoplasmic reticulum (ER) lumen, to their nascent neurotransmitter receptors and facilitating receptor biogenesis. Here we discuss proof-of-concept evidence that small molecules can selectively facilitate the biogenesis of their targets and examine the specific evidence in support of cognate ligand chaperoning of neurotransmitter receptor biogenesis.
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Affiliation(s)
- Nancy J Leidenheimer
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences CenterShreveport, LA, United States
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38
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Shiwarski DJ, Darr M, Telmer CA, Bruchez MP, Puthenveedu MA. PI3K class II α regulates δ-opioid receptor export from the trans-Golgi network. Mol Biol Cell 2017; 28:2202-2219. [PMID: 28566554 PMCID: PMC5531736 DOI: 10.1091/mbc.e17-01-0030] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 04/26/2017] [Accepted: 05/23/2017] [Indexed: 12/20/2022] Open
Abstract
The interplay between signaling and trafficking by G protein-coupled receptors (GPCRs) has focused mainly on endocytic trafficking. Whether and how surface delivery of newly synthesized GPCRs is regulated by extracellular signals is less understood. Here we define a signaling-regulated checkpoint at the trans-Golgi network (TGN) that controls the surface delivery of the delta opioid receptor (δR). In PC12 cells, inhibition of phosphoinositide-3 kinase (PI3K) activity blocked export of newly synthesized δR from the Golgi and delivery to the cell surface, similar to treatment with nerve growth factor (NGF). Depletion of class II phosphoinositide-3 kinase α (PI3K C2A), but not inhibition of class I PI3K, blocked δR export to comparable levels and attenuated δR-mediated cAMP inhibition. NGF treatment displaced PI3K C2A from the Golgi and optogenetic recruitment of the PI3K C2A kinase domain to the TGN-induced δR export downstream of NGF. Of importance, PI3K C2A expression promotes export of endogenous δR in primary trigeminal ganglion neurons. Taken together, our results identify PI3K C2A as being required and sufficient for δR export and surface delivery in neuronal cells and suggest that it could be a key modulator of a novel Golgi export checkpoint that coordinates GPCR delivery to the surface.
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Affiliation(s)
- Daniel J Shiwarski
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Marlena Darr
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Cheryl A Telmer
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Marcel P Bruchez
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213.,Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Manojkumar A Puthenveedu
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213 .,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213
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39
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
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Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
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40
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Goth CK, Tuhkanen HE, Khan H, Lackman JJ, Wang S, Narimatsu Y, Hansen LH, Overall CM, Clausen H, Schjoldager KT, Petäjä-Repo UE. Site-specific O-Glycosylation by Polypeptide N-Acetylgalactosaminyltransferase 2 (GalNAc-transferase T2) Co-regulates β 1-Adrenergic Receptor N-terminal Cleavage. J Biol Chem 2017; 292:4714-4726. [PMID: 28167537 PMCID: PMC5377785 DOI: 10.1074/jbc.m116.730614] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 01/29/2017] [Indexed: 01/08/2023] Open
Abstract
The β1-adrenergic receptor (β1AR) is a G protein-coupled receptor (GPCR) and the predominant adrenergic receptor subtype in the heart, where it mediates cardiac contractility and the force of contraction. Although it is the most important target for β-adrenergic antagonists, such as β-blockers, relatively little is yet known about its regulation. We have shown previously that β1AR undergoes constitutive and regulated N-terminal cleavage participating in receptor down-regulation and, moreover, that the receptor is modified by O-glycosylation. Here we demonstrate that the polypeptide GalNAc-transferase 2 (GalNAc-T2) specifically O-glycosylates β1AR at five residues in the extracellular N terminus, including the Ser-49 residue at the location of the common S49G single-nucleotide polymorphism. Using in vitro O-glycosylation and proteolytic cleavage assays, a cell line deficient in O-glycosylation, GalNAc-T-edited cell line model systems, and a GalNAc-T2 knock-out rat model, we show that GalNAc-T2 co-regulates the metalloproteinase-mediated limited proteolysis of β1AR. Furthermore, we demonstrate that impaired O-glycosylation and enhanced proteolysis lead to attenuated receptor signaling, because the maximal response elicited by the βAR agonist isoproterenol and its potency in a cAMP accumulation assay were decreased in HEK293 cells lacking GalNAc-T2. Our findings reveal, for the first time, a GPCR as a target for co-regulatory functions of site-specific O-glycosylation mediated by a unique GalNAc-T isoform. The results provide a new level of β1AR regulation that may open up possibilities for new therapeutic strategies for cardiovascular diseases.
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Affiliation(s)
- Christoffer K Goth
- From the Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Hanna E Tuhkanen
- the Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, P.O. Box 5000, FI-90014 Oulu, Finland
| | - Hamayun Khan
- the Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, P.O. Box 5000, FI-90014 Oulu, Finland
| | - Jarkko J Lackman
- the Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, P.O. Box 5000, FI-90014 Oulu, Finland
| | - Shengjun Wang
- From the Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Yoshiki Narimatsu
- From the Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Lasse H Hansen
- the Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, DK-2100 Copenhagen Ø, Denmark and
| | - Christopher M Overall
- the Centre for Blood Research, Department of Oral Biological and Medical Sciences, and Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Henrik Clausen
- From the Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Katrine T Schjoldager
- From the Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark,
| | - Ulla E Petäjä-Repo
- the Medical Research Center Oulu, Research Unit of Biomedicine, University of Oulu, P.O. Box 5000, FI-90014 Oulu, Finland,
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A PTEN-Regulated Checkpoint Controls Surface Delivery of δ Opioid Receptors. J Neurosci 2017; 37:3741-3752. [PMID: 28264976 DOI: 10.1523/jneurosci.2923-16.2017] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 01/26/2017] [Accepted: 02/14/2017] [Indexed: 12/13/2022] Open
Abstract
The δ opioid receptor (δR) is a promising alternate target for pain management because δR agonists show decreased abuse potential compared with current opioid analgesics that target the μ opioid receptor. A critical limitation in developing δR as an analgesic target, however, is that δR agonists show relatively low efficacy in vivo, requiring the use of high doses that often cause adverse effects, such as convulsions. Here we tested whether intracellular retention of δR in sensory neurons contributes to this low δR agonist efficacy in vivo by limiting surface δR expression. Using direct visualization of δR trafficking and localization, we define a phosphatase and tensin homolog (PTEN)-regulated checkpoint that retains δR in the Golgi and decreases surface delivery in rat and mice sensory neurons. PTEN inhibition releases δR from this checkpoint and stimulates delivery of exogenous and endogenous δR to the neuronal surface both in vitro and in vivo PTEN inhibition in vivo increases the percentage of TG neurons expressing δR on the surface and allows efficient δR-mediated antihyperalgesia in mice. Together, we define a critical role for PTEN in regulating the surface delivery and bioavailability of the δR, explain the low efficacy of δR agonists in vivo, and provide evidence that active δR relocation is a viable strategy to increase δR antinociception.SIGNIFICANCE STATEMENT Opioid analgesics, such as morphine, which target the μ opioid receptor (μR), have been the mainstay of pain management, but their use is highly limited by adverse effects and their variable efficacy in chronic pain. Identifying alternate analgesic targets is therefore of great significance. Although the δ opioid receptor (δR) is an attractive option, a critical limiting factor in developing δR as a target has been the low efficacy of δR agonists. Why δR agonists show low efficacy is still under debate. This study provides mechanistic and functional data that intracellular localization of δR in neurons is a key factor that contributes to low agonist efficacy, and presents a proof of mechanism that relocating δR improves efficacy.
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42
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Beerepoot P, Nazari R, Salahpour A. Pharmacological chaperone approaches for rescuing GPCR mutants: Current state, challenges, and screening strategies. Pharmacol Res 2017; 117:242-251. [DOI: 10.1016/j.phrs.2016.12.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 12/11/2022]
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43
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St-Louis É, Degrandmaison J, Grastilleur S, Génier S, Blais V, Lavoie C, Parent JL, Gendron L. Involvement of the coatomer protein complex I in the intracellular traffic of the delta opioid receptor. Mol Cell Neurosci 2016; 79:53-63. [PMID: 28041939 DOI: 10.1016/j.mcn.2016.12.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 12/01/2016] [Accepted: 12/26/2016] [Indexed: 11/16/2022] Open
Abstract
The delta opioid receptor (DOPr) is known to be mainly expressed in intracellular compartments. It remains unknown why DOPr is barely exported to the cell surface, but it seems that a substantial proportion of the immature receptor is trapped within the endoplasmic reticulum (ER) and the Golgi network. In the present study, we performed LC-MS/MS analysis to identify putative protein partners involved in the retention of DOPr. Analysis of the proteins co-immunoprecipitating with Flag-DOPr in transfected HEK293 cells revealed the presence of numerous subunits of the coatomer protein complex I (COPI), a vesicle-coating complex involved in recycling resident proteins from the Golgi back to the ER. Further analysis of the amino acid sequence of DOPr identified multiple consensus di-lysine and di-arginine motifs within the intracellular segments of DOPr. Using cell-surface ELISA and GST pulldown assays, we showed that DOPr interacts with COPI through its intracellular loops 2 and 3 (ICL2 and ICL3, respectively) and that the mutation of the K164AK166 (ICL2) or K250EK252 (ICL3) putative COPI binding sites increased the cell-surface expression of DOPr in transfected cells. Altogether, our results indicate that COPI is a binding partner of DOPr and provide a putative mechanism to explain why DOPr is highly retained inside the cells.
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Affiliation(s)
- Étienne St-Louis
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Jade Degrandmaison
- Département de médecine, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Sébastien Grastilleur
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Samuel Génier
- Département de médecine, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Véronique Blais
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Christine Lavoie
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada
| | - Jean-Luc Parent
- Département de médecine, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada.
| | - Louis Gendron
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Département d'anesthésiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada; Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada; Centre de recherche du CHUS, Sherbrooke, Québec, Canada; Quebec Pain Research Network, Québec, Canada.
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44
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Beerepoot P, Lam VM, Salahpour A. Pharmacological Chaperones of the Dopamine Transporter Rescue Dopamine Transporter Deficiency Syndrome Mutations in Heterologous Cells. J Biol Chem 2016; 291:22053-22062. [PMID: 27555326 DOI: 10.1074/jbc.m116.749119] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Indexed: 11/06/2022] Open
Abstract
A number of pathological conditions have been linked to mutations in the dopamine transporter gene, including hereditary dopamine transporter deficiency syndrome (DTDS). DTDS is a rare condition that is caused by autosomal recessive loss-of-function mutations in the dopamine transporter (DAT), which often affects transporter trafficking and folding. We examined the possibility of using pharmacological chaperones of DAT to rescue DTDS mutations. After screening a set of known DAT ligands for their ability to increase DAT surface expression, we found that bupropion and ibogaine increased DAT surface expression, whereas others, including cocaine and methylphenidate, had no effect. Bupropion and ibogaine increased wild type DAT protein levels and also promoted maturation of the endoplasmic reticulum (ER)-retained DAT mutant K590A. Rescue of K590A could be blocked by inhibiting ER to Golgi transport using brefeldin A. Furthermore, knockdown of coat protein complex II (COPII) component SEC24D, which is important in the ER export of wild type DAT, also blocked the rescue effects of bupropion and ibogaine. These data suggest that bupropion and ibogaine promote maturation of DAT by acting as pharmacological chaperones in the ER. Importantly, both drugs rescue DAT maturation and functional activity of the DTDS-associated mutations A314V and R445C. Together, these results are the first demonstration of pharmacological chaperoning of DAT and suggest this may be a viable approach to increase DAT levels in DTDS and other conditions associated with reduced DAT function.
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Affiliation(s)
- Pieter Beerepoot
- From the Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Vincent M Lam
- From the Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Ali Salahpour
- From the Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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Convertino M, Das J, Dokholyan NV. Pharmacological Chaperones: Design and Development of New Therapeutic Strategies for the Treatment of Conformational Diseases. ACS Chem Biol 2016; 11:1471-89. [PMID: 27097127 DOI: 10.1021/acschembio.6b00195] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Errors in protein folding may result in premature clearance of structurally aberrant proteins, or in the accumulation of toxic misfolded species or protein aggregates. These pathological events lead to a large range of conditions known as conformational diseases. Several research groups have presented possible therapeutic solutions for their treatment by developing novel compounds, known as pharmacological chaperones. These cell-permeable molecules selectively provide a molecular scaffold around which misfolded proteins can recover their native folding and, thus, their biological activities. Here, we review therapeutic strategies, clinical potentials, and cost-benefit impacts of several classes of pharmacological chaperones for the treatment of a series of conformational diseases.
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Affiliation(s)
- Marino Convertino
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
| | - Jhuma Das
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
| | - Nikolay V. Dokholyan
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
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Upadhyaya JD, Chakraborty R, Shaik FA, Jaggupilli A, Bhullar RP, Chelikani P. The Pharmacochaperone Activity of Quinine on Bitter Taste Receptors. PLoS One 2016; 11:e0156347. [PMID: 27223611 PMCID: PMC4880206 DOI: 10.1371/journal.pone.0156347] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 05/12/2016] [Indexed: 11/19/2022] Open
Abstract
Bitter taste is one of the five basic taste sensations which is mediated by 25 bitter taste receptors (T2Rs) in humans. The mechanism of bitter taste signal transduction is not yet elucidated. The cellular processes underlying T2R desensitization including receptor internalization, trafficking and degradation are yet to be studied. Here, using a combination of molecular and pharmacological techniques we show that T2R4 is not internalized upon agonist treatment. Pretreatment with bitter agonist quinine led to a reduction in subsequent quinine-mediated calcium responses to 35 ± 5% compared to the control untreated cells. Interestingly, treatment with different bitter agonists did not cause internalization of T2R4. Instead, quinine treatment led to a 2-fold increase in T2R4 cell surface expression which was sensitive to Brefeldin A, suggesting a novel pharmacochaperone activity of quinine. This phenomenon of chaperone activity of quinine was also observed for T2R7, T2R10, T2R39 and T2R46. Our results suggest that the observed action of quinine for these T2Rs is independent of its agonist activity. This study provides novel insights into the pharmacochaperone activity of quinine and possible mechanism of T2R desensitization, which is of fundamental importance in understanding the mechanism of bitter taste signal transduction.
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Affiliation(s)
- Jasbir D. Upadhyaya
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, R3E 3P4, Canada
| | - Raja Chakraborty
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, R3E 3P4, Canada
| | - Feroz A. Shaik
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, R3E 3P4, Canada
| | - Appalaraju Jaggupilli
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, R3E 3P4, Canada
| | - Rajinder P. Bhullar
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
| | - Prashen Chelikani
- Department of Oral Biology, and Manitoba Chemosensory Biology (MCSB) Research group, University of Manitoba, Winnipeg, MB, R3E 0W2, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, R3E 3P4, Canada
- * E-mail:
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47
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Doly S, Shirvani H, Gäta G, Meye F, Emerit MB, Enslen H, Achour L, Pardo-Lopez L, Kwon YS, Armand V, Gardette R, Giros B, Gassmann M, Bettler B, Mameli M, Darmon M, Marullo S. GABAB receptor cell-surface export is controlled by an endoplasmic reticulum gatekeeper. Mol Psychiatry 2016; 21:480-90. [PMID: 26033241 PMCID: PMC4828513 DOI: 10.1038/mp.2015.72] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/24/2015] [Accepted: 04/28/2015] [Indexed: 12/20/2022]
Abstract
Endoplasmic reticulum (ER) release and cell-surface export of many G protein-coupled receptors (GPCRs) are tightly regulated. For gamma-aminobutyric acid (GABA)B receptors of GABA, the major mammalian inhibitory neurotransmitter, the ligand-binding GB1 subunit is maintained in the ER by unknown mechanisms in the absence of hetero-dimerization with the GB2 subunit. We report that GB1 retention is regulated by a specific gatekeeper, PRAF2. This ER resident transmembrane protein binds to GB1, preventing its progression in the biosynthetic pathway. GB1 release occurs upon competitive displacement from PRAF2 by GB2. PRAF2 concentration, relative to that of GB1 and GB2, tightly controls cell-surface receptor density and controls GABAB function in neurons. Experimental perturbation of PRAF2 levels in vivo caused marked hyperactivity disorders in mice. These data reveal an unanticipated major impact of specific ER gatekeepers on GPCR function and identify PRAF2 as a new molecular target with therapeutic potential for psychiatric and neurological diseases involving GABAB function.
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Affiliation(s)
- Stéphane Doly
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Hamasseh Shirvani
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Gabriel Gäta
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Frank Meye
- Institut du Fer à Moulin
Université Pierre et Marie Curie - Paris 6INSERM17 Rue du fer à moulin 75005 Paris
| | - Michel-Boris Emerit
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Hervé Enslen
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Lamia Achour
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Liliana Pardo-Lopez
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Yang Seung Kwon
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Vincent Armand
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Robert Gardette
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Bruno Giros
- Physiopathologie des Maladies du Système Nerveux Central
Université Pierre et Marie Curie - Paris 6INSERMCentre National de la Recherche ScientifiqueBâtiment B, 4ème étage, case courrier 37 9 Quai Saint Bernard 75252 Paris Cedex 05
- Service Psychiatrie
McGill University [Montréal]Institut Universitaire en Santé Mentale Douglas6875 Boulevard Lasalle, Montréal, QC H4H 1R2
| | - Martin Gassmann
- Department of Biomedicine
University of Basel Petersplatz 1, 4003 Basel
| | - Bernhard Bettler
- Department of Biomedicine
University of Basel Petersplatz 1, 4003 Basel
| | - Manuel Mameli
- Institut du Fer à Moulin
Université Pierre et Marie Curie - Paris 6INSERM17 Rue du fer à moulin 75005 Paris
| | - Michèle Darmon
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Stefano Marullo
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
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48
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Mattila SO, Tuusa JT, Petäjä-Repo UE. The Parkinson's-disease-associated receptor GPR37 undergoes metalloproteinase-mediated N-terminal cleavage and ectodomain shedding. J Cell Sci 2016; 129:1366-77. [PMID: 26869225 DOI: 10.1242/jcs.176115] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 02/08/2016] [Indexed: 12/20/2022] Open
Abstract
The G-protein-coupled receptor 37 ( GPR37) has been implicated in the juvenile form of Parkinson's disease, in dopamine signalling and in the survival of dopaminergic cells in animal models. The structure and function of the receptor, however, have remained enigmatic. Here, we demonstrate that although GPR37 matures and is exported from the endoplasmic reticulum in a normal manner upon heterologous expression in HEK293 and SH-SY5Y cells, its long extracellular N-terminus is subject to metalloproteinase-mediated limited proteolysis between E167 and Q168. The proteolytic processing is a rapid and efficient process that occurs constitutively. Moreover, the GPR37 ectodomain is released from cells by shedding, a phenomenon rarely described for GPCRs. Immunofluorescence microscopy further established that although full-length receptors are present in the secretory pathway until the trans-Golgi network, GPR37 is expressed at the cell surface predominantly in the N-terminally truncated form. This notion was verified by flow cytometry and cell surface biotinylation assays. These new findings on the GPR37 N-terminal limited proteolysis may help us to understand the role of this GPCR in the pathophysiology of Parkinson's disease and in neuronal function in general.
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Affiliation(s)
- S Orvokki Mattila
- Medical Research Center Oulu, and Cancer and Translational Medicine Research Unit, University of Oulu, Oulu FI-90014, Finland
| | - Jussi T Tuusa
- Medical Research Center Oulu, and Cancer and Translational Medicine Research Unit, University of Oulu, Oulu FI-90014, Finland
| | - Ulla E Petäjä-Repo
- Medical Research Center Oulu, and Cancer and Translational Medicine Research Unit, University of Oulu, Oulu FI-90014, Finland
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49
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Upadhyaya J, Singh N, Bhullar RP, Chelikani P. The structure–function role of C-terminus in human bitter taste receptor T2R4 signaling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1502-8. [DOI: 10.1016/j.bbamem.2015.03.035] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/10/2015] [Accepted: 03/31/2015] [Indexed: 11/15/2022]
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50
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Conn PM, Spicer TP, Scampavia L, Janovick JA. Assay strategies for identification of therapeutic leads that target protein trafficking. Trends Pharmacol Sci 2015; 36:498-505. [PMID: 26067100 DOI: 10.1016/j.tips.2015.05.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 05/09/2015] [Accepted: 05/13/2015] [Indexed: 12/12/2022]
Abstract
Receptors, enzymes, and ion channels are traditional targets of therapeutic development. A common strategy is to target these proteins with agents that either activate or suppress their activity with ligands or substrates that occupy orthosteric sites or have allosteric interactions. An alternative approach involves regulation of protein trafficking. In principle, this approach enables 'rescue' of misfolded and misrouted mutant proteins to restore function, 'shipwrecking' of undesirable proteins by targeting them for destruction, and regulation of levels of partially expressed wild type (WT) proteins at their functional sites of action. Here, we present drug discovery strategies that identify 'pharmacoperones', which are small molecules that serve as molecular templates and cause otherwise misfolded mutant proteins to fold and route correctly.
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Affiliation(s)
- P Michael Conn
- Department of Internal Medicine, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Department of Cell Biology/Biochemistry, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
| | - Timothy P Spicer
- Lead Identification Division, Translational Research Institute and Department of Molecular Therapeutics, Scripps Research Institute, Jupiter, FL, USA
| | - Louis Scampavia
- Lead Identification Division, Translational Research Institute and Department of Molecular Therapeutics, Scripps Research Institute, Jupiter, FL, USA
| | - Jo Ann Janovick
- Department of Internal Medicine, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Department of Cell Biology/Biochemistry, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, USA
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